*{
    margin: 0;
    padding: 0;
    list-style: none;
}
/* 导航栏 */
.nav{
    /* position: relative; */
    /* float: right; */
    height: 60px;
    width: 100%;
    margin: 0 auto;
    background: linear-gradient(45deg,rgb(74, 94, 110),rgb(93, 97, 105));
}
.page>img{
    margin: 0 40px;
    float: left;
    /* top: -10px; */
    width: 200px;
    height: 60px;
}
a{
    color:rgb(14, 16, 32);
    display: block;
    text-decoration: none;
}
.nav li{
    left: 50px;
    position: relative;
    width: 10%;
    height: 100%;
    line-height: 60px;
    letter-spacing: 2px;
    float: left;
    /* color: rgb(30, 36, 61); */
    margin: 0 auto;
    text-align: center;
    cursor: pointer;

}
.nav>li>a:hover{
    color: rgb(228, 243, 255);
    background-color: rgb(53, 70, 107);
}
.top>img{
    width: 100%;
}
/* 滑动图片 */
.container{

    /**弹性布局 让页面元素垂直+水平居中  */
    display: flex;
    justify-content: center;
    align-items: center;
    /* 让页面高度占浏览器可视区域高度 */
    width: 1000px;
    height: 800px;
    /* height: 100vh; */
    margin: 0 auto;
}
.container ul{
    list-style: none;
    position: relative;
    width: 100%;
    height: 98%;
    display: flex;
    /* 让子元素平均分配宽度 */
    justify-content: space-between;
    align-items: flex-end;
}
/* 小图片 start*/
.container ul li{
    width: 200px;
    cursor: pointer;
}
.container ul li img{
    width: 100%;
    height: 25%;
    /* 加透明边框 */
    border: 5px solid transparent;

}
/* 小图片 end */

/* 大图片 start */
.container ul .bigImg{
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 550px;
    border: 5px solid transparent;
    background: url("../images/h1.jpg") no-repeat;
    background-size: cover; 
    transition: all 0.5s;
}
/* 大图片 end */

/* 移动框 */
.container ul .frame{
    position: absolute;
    left:0;
    bottom: 4px;
    width: 195px;
    height: 200px;
    border: 5px solid rgb(199, 193, 192);

    pointer-events: none;
    /* 加过渡 */
    transition: all 0.5s;
}
/* 用伪元素做三角 */
.container ul .frame::before{
    content: "";
    position: absolute;
    /* calc 自动计算让三角盒子水平居中 */
    top: -19px;
    left: calc(50% - 15px);
    width: 30px;
    height: 15px;
    background-color: rgb(189, 182, 182);
    clip-path: polygon(0 100%,50% 0,100% 100%);
}
.container ul li:nth-child(1):hover ~ .bigImg{
    background-image: url("../images/h1.jpg") ;
}
.container ul li:nth-child(1):hover ~ .frame{
    left: 0;
}
.container ul li:nth-child(2):hover ~ .bigImg{
    background-image: url("../images/h2.jpg") ;
}
.container ul li:nth-child(2):hover ~ .frame{
    left: 267px;
}
.container ul li:nth-child(3):hover ~ .bigImg{
    background-image: url("../images/h3.jpg") ;
}.container ul li:nth-child(3):hover ~ .frame{
    left: 534px;
}
.container ul li:nth-child(4):hover ~ .bigImg{
    background-image: url("../images/h4.jpg");
}
.container ul li:nth-child(4):hover ~ .frame{
    left: 801px;
}
